Standard or premium: Which dog food has more mycotoxins?

Are the cheap versions of pet food less safe to feed dogs if we look at presence of mycotoxins? Brazilian researchers put this to the test.

The Brazilian pet food sector is growing and several type of pet foods are on the market. At the same time, the issue concerning safety of dry dog feed has become a topic of widespread international interest. One of the safety issues is the presence of mycotoxins. Fumonisins (Fum), zearalenone (Zea) and aflatoxins (Afla) have been detected in cereals and grains worldwide and their presence in pet food represents a risk for pet health.

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Different price ranges tested

In the present study, researchers evaluated the safety of low and high cost dry feed and the degree of exposure of dogs to mycotoxins through naturally contaminated feed in Brazil. The study has been published in the latest edition of the World Mycotoxin Journal. Fum, Zea and Afla were analysed in three pet food types intended for dogs (n=87). The food samples were provided by the pet owners and were common brands retailed in Brazil, including those exported abroad.

According to the information declared on the label of the dry dog food, the samples were grouped into:

How much mycotoxins can a dog take?

The researchers also published the pet safe dietary level (SPDL) in their paper. Considering that the dose which causes lung lesions (LOAEL) in swine is 400 µg FB1/kg BW/day (EFSA, 2005; Zomborszky-Kovács et al., 2002a), the calculated SPDL was 2,000 µg fumonisins/kg dog foodd. The dosage of 75.0 µg /kg BW/day has been adopted as LOAEL for Zea. Therefore, the calculated SPDL was 375 µg /kg dog food. SPDL for aflatoxins was not calculated because a no-effect level (NOEL) could not be established from the available data (EFSA, 2004).

Conclusion

Although the food samples intended for dogs in Paraná State, Brazil, were often contaminated with aflatoxins, fumonisins and Zea, the estimated daily intake values were low, even for the Standard feed (low cost formulations). However, the paper states that it cannot be excluded that some of the pet food samples could have a negative effect on animal health and performance considering feeding a mono-diet of commercial feed, low multi-mycotoxin contamination levels and interactions between mycotoxins. Therefore, the researchers address that the risk assessment approaches for these mycotoxins in pet food should consider their possible synergic or additive effects. In Brazil, and in most countries, there are no specific guidelines for the maximum tolerated limits for mycotoxins in pet food. Nevertheless, the results obtained in this study highlight that specific legislation, monitoring and control of mycotoxin levels in pet feed are essential in order to improve the safety and quality of the end product and minimise animal health hazards.